On Sun, 1 Mar 2009 07:57:30 -0700, "SteveB"
wrote:

Take a look at this. It will explain the shape, and why they wouldn't be
remachined on the ends.


http://www.petrodrillingtools.com/pr...FRBbagodwGo8lg

Steve

Actually...most are buttress thread and can be remachined a bit.

http://en.wikipedia.org/wiki/Buttress_thread
http://www-odp.tamu.edu/publications..._s/drill_s.htm
http://en.wikipedia.org/wiki/Drill_string



"Tim Wescott" wrote in message
...
On Sat, 28 Feb 2009 21:06:20 -0700, SteveB wrote:

I don't have a clue why, but just a short time ago, I was lying in my
hot bath contemplating time spent on drilling rigs. I've come to
realize that I've forgotten more than most young guys know. But I
digress.

Question: Why is it that 5" drill pipe comes in random lengths. Every
crane operator had that denim covered tally book in their back pocket,
and losing it could bring on severe consequences.

Out of everything we used, jars, collars, stabilizers, saver subs,
fishing tools, ........... the thing there was the most of was drilling
pipe, and that would seem to be the easiest to fabricate in standard
lengths. Same with casing.

Can anyone tell me?

Steve

It's always getting cut off and the ends remachined?

(I know nothing of oil drilling)

--
http://www.wescottdesign.com


"Lenin called them "useful idiots," those people living in
liberal democracies who by giving moral and material support
to a totalitarian ideology in effect were braiding the rope that
would hang them. Why people who enjoyed freedom and prosperity worked
passionately to destroy both is a fascinating question, one still with us
today. Now the useful idiots can be found in the chorus of appeasement,
reflexive anti-Americanism, and sentimental idealism trying to inhibit
the necessary responses to another freedom-hating ideology, radical Islam"

Bruce C. Thornton, a professor of Classics at American University of Cal State Fresno